/**
 * @author 杜伟毅
 * @version 1.0
 * @since 2024/11/12
 */

class A{
    int m;
    int getM(){
        return m;
    }
    int seeM(){
        return m;
    }
}
class B extends A{
    int m;
    int getM(){
        return m+100;
    }
}
public class Test {
    public static void main(String[] args) {
        B b = new B();
        A a=b;
        a.m=-100;
        System.out.println(a.getM());
        System.out.println(b.seeM());
    }
}
